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Being miserable and treating other people like dirt is every New Yorker's God-given right.
— The Mayor • Ghostbusters II

Behind the line May contain spoilers.
Our reading
An editorial interpretation.
The speaker sarcastically frames grumpiness and rudeness as a kind of civic tradition, an entitlement bestowed from above on city dwellers. The joke is that surliness gets treated as a proud local right, half insult and half affectionate boast about a famously tough, unfriendly place.
Context reviewed